Well the skill in question was "Sweeping" and was one of gryz's skills. To be very honest I consider myself to be an expert at this game and I have NEVER throughout perhaps 20 playthroughs of the game seen gryz with this ability.
I know this game as well as anyone who has on there own explored every facet of the game by themselves. I can answer perhaps any piece of trivia based on game play of this game without a hitch. Except that.....well and one other thing, In the manual it describes one skill that again i have never seen....I forget whats its called and i really don't feel like digging to find the book....if i remember correctly "I think" it was called Blast....I just assumed it was one of Alys's abilities that i never unlocked because I didn't levels before she........leaves your party. Also I Leveled ALOT the first time i played this simply because i didn't know how to equip items. thats right, i played through up through the juza fight with everyones starting equipment. I did actually kill up to zio in the same fasion....However never past there, it was a rental and as fate would have it the cartridges battery was dead so save files would disappear when i turned off the console. (consider that 13yo BURN session, from beginning to zios death with only starting equipment with a break.....I was not challenging myself i really thought the game was that hard.)
Anyways back OT, Were do you acquire sweeping? is there a difference between pal and american? is it a hacked skill?
Gryz learns Sweeping at... maybe... level 27 or so? He'll definitely have it for the end of the game, though. Several of it for that matter. As for the skill in the manual, you are likely thinking of Bolt, which I believe is in fact Vol, so it should be listed as a Technique. On the other hand, Death and Eliminate also qualify as very close to the descriptors of that Bolt skill, so I dunno...
Sweeping is obtained when Gryz reaches level 25, meaning that if you level up a LOT, he'll get it before you butt heads with Zio for real. It's Gryz' version of Airslash, no more no less, sans the compatibility with Phononmezer to form Silent Wave. (which is unfortunate, since a War-cried Silent Wave would hurt plenty)
He'll definitely have a whole stack of Sweeping charges by the time you go stomp out P-Darky, so if you've missed the skill up to now, you've either:
- Never used Gryz for the final battle.
- Used Gryz for the final battle, but never used any of his skills after getting him back in your party. (since he only has 3 skills, his skill window does not scroll and coming across Sweeping on the way to War Cry or Crash would be impossible)